ACE and Hypertension: Recently, several clinical studies have found a reduced incidence of tumors treated with the antidiabetic agent metformin [47], patients with hypertension treated with beta blockers [48], angiotensin receptor blockers (ARBs) losartan [49] and angiotensin-converting enzyme inhibitors [50], as well as potential antiproliferative and proapoptotic effects of these treatments.